A conventional network monitoring system receives the performance measurement data and the status notification data in huge quantities that are constantly transmitted from the respective devices constructing the network. An operator, who monitors the network, improves the performance of the network by changing a device parameter of each device or expanding the processing abilities on the basis of the performance measurement data and the status notification data that are received by the network monitoring system.
However, the performance measurement data received by the network monitoring system includes the data that are not effective for improving the performance of the network. For example, it includes the performance measurement data that is measured in deterioration of the network caused by a fault that occurs to one of the devices and a fault that occurs to a transmission line connecting the devices to one another. In such a case, improvement of the network performance is not achieved by changing the device parameter of the device or expanding the processing abilities or the like. Therefore, the operator needs to eliminate the performance measurement data that is not effective for improvement of the network performance.
According to the conventional network monitoring system, the performance measurement data and the status notification data of each device are collected separately. Therefore, the operator checks whether or not a time, when the performance measurement data of each device is measured, is in a period of time, when a fault of the device or a fault of the network occurs, referring to a history of the status notification data of each device in accordance with know how that the operator has. Then, the operator filters the received performance measurement data by eliminating the performance measurement data that is not effective for improvement of the network performance. Such operation for eliminating the performance measurement data requires lots of steps and lots of manpower.
The operator analyzes the filtered performance measurement data after such filtering of the performance measurement data, and maintains the performance of the network optimum by setting a parameter of each device constructing the network at an optimum value, changing the construction of the network, or expanding the device processing abilities or the like.
[Patent Reference 1] Japanese Patent Application Laying Open (KOHYO) No. 2001-519619
[Patent Reference 2] Japanese Patent Application Laying Open (KOKAI) No. 11-261471